1. Field of the Invention
The present invention relates to a mobile terminal apparatus or a terminal device used complexly with the mobile terminal apparatus, and more particularly, to an apparatus and method of controlling an information process system of a mobile terminal apparatus using a flash memory, which is capable of protecting a user-set data by using the flash memory.
2. Description of the Related Art
Mobile terminal apparatuses, such as a cellular phone, a personal digital assistant (PDA), a hand-held PC (HPC), etc., have been popularized by their capability to store information, function like a computer, and transmit data, including an audio signal, through a communication channel, and their portability.
FIG. 3 is a block diagram of an apparatus controlling an information process system of the above-described mobile terminal apparatus. As shown in FIG. 3, the apparatus controlling the information process system includes a backup battery 400, a CPU 100, a flash memory 500 and a main memory 300. The information process system of the mobile terminal apparatus further comprises a main battery, a battery switching portion, and a display portion (not shown).
The CPU 100 controls the information process system of the mobile terminal apparatus. Typically, the main memory 300 is a dynamic RAM (DRAM), and stores data that is set by a user during the operation of the mobile terminal apparatus and stores running programs. The data stored in the DRAM is deleted when power is turned off. The flash memory 500 is a non-volatile memory comprising a flash read only memory (ROM) and an electrically erasable and programmable ROM (EEPROM). The data stored in the flash memory 500 is still retained when the power is turned off. The flash memory 500 holds/stores boot data that is used in booting the information process system of the terminal apparatus, and stores boot application program data. For example, the flash memory 500 retains the boot data, etc., therein after the data has been copied to another memory, such as the main memory 300, for execution.
The main battery (not shown) provides main power for operating the mobile terminal apparatus. The backup battery 400 provides auxiliary power to the main memory 300 of the mobile terminal apparatus when the main power is turned off. The battery switching portion (not shown) is switched to supply the main power from the main battery to the mobile terminal apparatus including the main memory 300 or to supply the auxiliary power from the backup battery 400 to the mobile terminal apparatus including the main memory 300.
When the power supplied to the information process system of the mobile terminal apparatus is lowered to (below) a predetermined level, the CPU 100 controls the battery switching portion to supply the auxiliary power from the backup battery 400 to the main memory 300.
The operation of the information process system of the mobile terminal apparatus as described above will be described in detail hereinbelow. The CPU 100 stores data that is externally transmitted or data that is input by a user in the main memory 300. The user-set data stored in the main memory 300, which is the DRAM, is deleted either when the power is turned off or when the power is lowered to a predetermined level. The power-off can occur due to a lowered power of the main battery and/or a sudden separation of the main battery from the mobile terminal apparatus.
To prevent the data stored in the main memory 300 from being deleted, the CPU 100 determines that the power of the main battery is lowered to the predetermined level during use of the mobile terminal apparatus, and then switching the mobile terminal apparatus to an unusable mode, for example, by blocking a communication with the external environment by disconnecting and/or staying disconnected. Then, the CPU 100 transmits a control signal to the battery switching portion to supply the auxiliary power from the backup battery 400 to the main memory 300. According to the above operation, the data stored in the main memory 300 is retained.
When the main battery is newly charged or replaced with a new battery, the CPU 100 controls the battery switching portion to supply the power to the mobile terminal apparatus from the main battery. By supplying power from the main battery, the CPU 100 initializes the mobile terminal apparatus to return the mobile terminal apparatus to a usable condition, for example, by allowing connection to the external environment.
Since the data stored in the main memory 300 is retained by the auxiliary power supplied from the backup battery 400, basic settings and displays are maintained with the same data set before the power is lowered to the predetermined level. However, if the mobile terminal apparatus is left for a long time in the condition that the power is not supplied from the main battery, the backup battery runs out of power and does not supply any more auxiliary power to the main memory 300. As a result, the data stored in the main memory 300 is deleted, and becomes unrecoverable even if the power is re-supplied, for example, from the main battery.
In the state that the data of the main memory 300 is deleted, when the power is re-supplied, the mobile terminal apparatus is initialized by boot data stored in the flash memory 500. At this time, since a default image is displayed by default image data that is stored as the boot data, and a menu of the mobile terminal apparatus is set by default menu data, there is a problem that the mobile terminal apparatus cannot be booted with the lost user-set data, so that, for example, the user is required to re-set a display image and an operation menu of the default boot data in the mobile terminal apparatus.